[228] Medical Chronicle, 1889, 89.
[229] Practitioner, 1889, ii. 15.
[230] Brit. Med. Journ., March 3, 1894.
Diagram of Visual Field.
C. F. W., aged 38, consulted Mr. Snell for his defective sight on April 9, 1892. He had been a mixer at a factory for the manufacture of explosives. He was jaundiced, the conjunctiva yellow, and the lips blue. He was short of breath, and after the day’s work experienced aching of the forearms and legs and tingling of the fingers. The urine was black in colour, of sp. gr. 1024; it was examined spectroscopically by Mr. MacMunn, who reported the black colour as due neither to indican, nor to blood, nor bile, but to be caused by some pigment belonging to the aromatic series. The patient’s sight had been failing since the previous Christmas. Vision in the right eye was 6⁄24, left 6⁄36, both optic papillæ were somewhat pale. In each eye there was a central scotoma for red, and contraction of the field (see [diagram]). The man gradually gave up the work, and ultimately seems to have recovered. It is, however, interesting to note that, after having left the work for some weeks, he went back for a single day to the “mixing,” and was taken very ill, being insensible and delirious for five hours.
§ 249. The Blood in Nitro-benzol Poisoning.—The effect on the blood has been specially studied by Huber.[231] The blood of rabbits poisoned by dinitro-benzol is of a dark chocolate colour, and the microscope shows destruction of the red corpuscles; the amount of destruction may be gathered from the following:—the blood corpuscles of a rabbit before the experiment numbered 5,588,000 per cubic centimetre; a day after the experiment 4,856,000; a day later 1,004,000; on the third day the rabbit died.